【摘要】 对暖温带落叶阔叶林生态系统主要乔木、灌木植物叶片中的碳稳定性碳同位素比率（δ１３Ｃ值）进行了测定和比较。结果显示，这些植物叶片的稳定性碳同位素比率（δ１３Ｃ）值受多种因子的影响，具有较大的种间差异及时空变化。主要表现在不同植物种叶片δ１３Ｃ值不同，排列顺序为山杏（Ｐｒｕｎｕｓａｒｍｅｎｉａｃａｖａｒ．ａｎｓｕＭａｘｉｍ．）（－２４．７５±０．８５‰）＞大叶白蜡（ＦｒａｘｉｎｕｓｒｈｙｎｃｈｏｐｈｙｌａＨｃｅ．）（－２５．９４±１．５２‰）≈荆条（Ｖｉｔｅｘｎｅｇｕｎｄｏｖａｒ．ｈｅｔｅｒｏｐｈｙｌａ（Ｆｒａｎｃｈ．）Ｒｅｈｄ．）（－２６．０１±１．６３‰）≈辽东栎（ＱｕｅｒｃｕｓｌｉａｏｔｕｎｇｅｎｓｉｓＫｏｉｚ．）（－２６．０７±１．１７‰）≈北京丁香（ＳｙｒｉｎｇａｐｅｋｉｎｅｎｓｉｓＲｕｐｒ．）（－２６．４６±０．８０‰）＞胡桃楸（ＪｕｇｌａｎｓｍａｎｄｓｈｕｒｉｃａＭａｘｉｍ．）（－２８．１１±１．５２‰）。生长初期叶片δ１３Ｃ值较生长末期高，尤以胡桃楸和辽东栎表现明显，其生长初期和末期的叶片δ１３Ｃ值相差皆达３‰。生境条件，特别是土壤水分含量和土层厚度，对植物叶片的δ１３Ｃ值的高低有较大影响，生长?更多还原

【Abstract】 The stable carbon isotope ratios ( δ 13 C) of dominant tree and shrub species in typical temperate broad leaved forests in Dongling Mountain, northwestern part of Beijng, China, were studied. The results indicated that the values of foliar δ 13 C differed among the species tested, in the following order of Prunus armeniaca var. ansu Maxim. > Fraxinus rhychophylla Hce. ≈ Vitex negundo var. heterophylla (Franch.) Rehd.≈ Quercus liaotungensis Koiz. ≈ Syringa pekinensis Rupr. > Juglans mandshurica Maxim. The δ 13 C values were also affected by the maturity of leaves. The newly developed leaves had higher δ 13 C values than the mature ones, especially in Juglans mandshurica and Quercus liaotungensis. The conditions of habitats, particularly soil depth and moisture content, also had pronounced effect on foliar δ 13 C. The foliar δ 13 C values of plants grown in dry habitats were higher than those in moist ones. They were also affected by the position of leaves in the canopy: leaves at upper canopy showed higher δ 13 C values than the lower ones. It is suggested that stable isotope technique may be effective for the study of ecophysiology of plants in the warm temperate regions of China.更多还原